<span>Every term is adding 3 to the previous term. Therefore, the terms are 2, 5, 8, 11, 14, 17, 20, 23, 26, 29 ... The tenth term is 29.</span>
The equation is 5c+25b=260 when c+b=12. rearrange that into 12-b=c. substitute and you get 5(12-b)+25b=260. b=10. 12-10=2, so 10 buses and 2 cars were used as transportation for the field trip.
Recall that the characteristic polynomial of a 2x2 matrix

is

but

and

, so the characteristic polynomial for

is

We're given that the trace is 15 and determinant is 50, so the characteristic polynomial for the matrix in question is

and the eigenvalues are those

for which the characteristic polynomial evaluates to 0.
I think it's right and scalene
It's a right triangle because it has a right angle and it's a scalene triangle because it has three unequal sides.